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	/*
	* Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package java.lang.management;

	import javax.management.openmbean.CompositeData;
	import sun.management.MonitorInfoCompositeData;

	/**
	* Information about an object monitor lock. An object monitor is locked
	* when entering a synchronization block or method on that object.
	*
	* <h3>MXBean Mapping</h3>
	* <tt>MonitorInfo</tt> is mapped to a {@link CompositeData CompositeData}
	* with attributes as specified in
	* the {@link #from from} method.
	*
	* @author Mandy Chung
	* @since 1.6
	*/
	public class MonitorInfo extends LockInfo {

	private int stackDepth;
	private StackTraceElement stackFrame;

	/**
	* Construct a <tt>MonitorInfo</tt> object.
	*
	* @param className the fully qualified name of the class of the lock object.
	* @param identityHashCode the {@link System#identityHashCode
	* identity hash code} of the lock object.
	* @param stackDepth the depth in the stack trace where the object monitor
	* was locked.
	* @param stackFrame the stack frame that locked the object monitor.
	* @throws IllegalArgumentException if
	* <tt>stackDepth</tt> ≥ 0 but <tt>stackFrame</tt> is <tt>null</tt>,
	* or <tt>stackDepth</tt> < 0 but <tt>stackFrame</tt> is not
	* <tt>null</tt>.
	*/
	public MonitorInfo(String className,
	int identityHashCode,
	int stackDepth,
	StackTraceElement stackFrame) {
	super(className, identityHashCode);
	if (stackDepth >= 0 && stackFrame == null) {
	throw new IllegalArgumentException("Parameter stackDepth is " +
	stackDepth + " but stackFrame is null");
	}
	if (stackDepth < 0 && stackFrame != null) {
	throw new IllegalArgumentException("Parameter stackDepth is " +
	stackDepth + " but stackFrame is not null");
	}
	this.stackDepth = stackDepth;
	this.stackFrame = stackFrame;
	}

	/**
	* Returns the depth in the stack trace where the object monitor
	* was locked. The depth is the index to the <tt>StackTraceElement</tt>
	* array returned in the {@link ThreadInfo#getStackTrace} method.
	*
	* @return the depth in the stack trace where the object monitor
	* was locked, or a negative number if not available.
	*/
	public int getLockedStackDepth() {
	return stackDepth;
	}

	/**
	* Returns the stack frame that locked the object monitor.
	*
	* @return <tt>StackTraceElement</tt> that locked the object monitor,
	* or <tt>null</tt> if not available.
	*/
	public StackTraceElement getLockedStackFrame() {
	return stackFrame;
	}

	/**
	* Returns a <tt>MonitorInfo</tt> object represented by the
	* given <tt>CompositeData</tt>.
	* The given <tt>CompositeData</tt> must contain the following attributes
	* as well as the attributes specified in the
	* <a href="LockInfo.html#MappedType">
	* mapped type</a> for the {@link LockInfo} class:
	* <blockquote>
	* <table border summary="The attributes and their types the given CompositeData contains">
	* <tr>
	* <th align=left>Attribute Name</th>
	* <th align=left>Type</th>
	* </tr>
	* <tr>
	* <td>lockedStackFrame</td>
	* <td><tt>CompositeData as specified in the
	* <a href="ThreadInfo.html#StackTrace">stackTrace</a>
	* attribute defined in the {@link ThreadInfo#from
	* ThreadInfo.from} method.
	* </tt></td>
	* </tr>
	* <tr>
	* <td>lockedStackDepth</td>
	* <td><tt>java.lang.Integer</tt></td>
	* </tr>
	* </table>
	* </blockquote>
	*
	* @param cd <tt>CompositeData</tt> representing a <tt>MonitorInfo</tt>
	*
	* @throws IllegalArgumentException if <tt>cd</tt> does not
	* represent a <tt>MonitorInfo</tt> with the attributes described
	* above.

	* @return a <tt>MonitorInfo</tt> object represented
	* by <tt>cd</tt> if <tt>cd</tt> is not <tt>null</tt>;
	* <tt>null</tt> otherwise.
	*/
	public static MonitorInfo from(CompositeData cd) {
	if (cd == null) {
	return null;
	}

	if (cd instanceof MonitorInfoCompositeData) {
	return ((MonitorInfoCompositeData) cd).getMonitorInfo();
	} else {
	MonitorInfoCompositeData.validateCompositeData(cd);
	String className = MonitorInfoCompositeData.getClassName(cd);
	int identityHashCode = MonitorInfoCompositeData.getIdentityHashCode(cd);
	int stackDepth = MonitorInfoCompositeData.getLockedStackDepth(cd);
	StackTraceElement stackFrame = MonitorInfoCompositeData.getLockedStackFrame(cd);
	return new MonitorInfo(className,
	identityHashCode,
	stackDepth,
	stackFrame);
	}
	}

	}

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